--- product_id: 604213502 title: "TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection" brand: "tt flex" price: "VT77673" currency: VUV in_stock: true reviews_count: 5 category: "Tt Flex" url: https://www.desertcart.vu/products/604213502-tt-flex-potable-thermal-expansion-tank-for-water-heater-4 store_origin: VU region: Vanuatu --- # appliance-grade corrosion-resistant finish 4.5-gallon capacity 100% butyl diaphragm & plastic liner TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection **Brand:** tt flex **Price:** VT77673 **Availability:** ✅ In Stock ## Summary > 🛠️ Upgrade your water heater’s safety with sleek, smart expansion! ## Quick Answers - **What is this?** TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection by tt flex - **How much does it cost?** VT77673 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.vu](https://www.desertcart.vu/products/604213502-tt-flex-potable-thermal-expansion-tank-for-water-heater-4) ## Best For - tt flex enthusiasts ## Why This Product - Trusted tt flex brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Backflow Blocker:** Stops hot water from backflowing into the cold water line, ensuring system efficiency and safety. - • **Pressure Guardian:** Prevents dangerous pressure build-ups, protecting your water heater and home from costly damage. - • **Compact Powerhouse:** Generous 4.5-gallon capacity fits seamlessly in tight spaces without compromising performance. - • **DIY-Friendly Design:** Easy to install for both pros and weekend warriors—upgrade your system hassle-free. - • **Rust-Resistant Armor:** Finished with appliance-quality paint to resist corrosion and maintain a sleek, professional look. ## Overview The TT FLEX 4.5-Gallon Thermal Expansion Tank is engineered to manage thermal expansion in water heaters by safely absorbing excess pressure. Featuring a durable 100% butyl diaphragm and corrosion-resistant appliance-grade finish, it prevents backflow and pressure relief valve leaks. Compact and easy to install, it’s the essential upgrade for protecting your water heating system and avoiding costly repairs. ## Description TT FLEX 4.5-Gallon Thermal Expansion Tank has a secure connection to water heaters that prevents dangerous build-ups of pressure. This water heater expansion tank stops hot water from backflowing into the cold water line and it also prevents hot water from escaping through the pressure relief valve and onto the floor. Constant fluctuations in water pressure can be dangerous and they can damage the water heater, properly installing a thermal expansion tank can solve all these issues. Review: All new plumbing in reno so added one inline. So far no issues. Good price. Pressure good so no worries. Easy to add into system Review: Funciona ## Features - TT FLEX water expansion tank is finished with appliance quality paint which helps prevent external corrosion and rust. This expansion tanks feature a 100% butyl diaphragm and plastic liner to separate the system water from the tanks air precharge. - Inline thermal expansion tank,accepts expanded water caused by thermal expansion. Returns water to the system when hot water is used,it prevents the relief valve from going off. - Easy to Install: The tank's compact size and easy-to-install design make it an ideal choice for both professional contractors and DIY enthusiasts alike. With its simple installation process, you can quickly and easily add this expansion tank to your system. - Ample Capacity: The TT FLEX water expansion tank has a generous 4.5-gallon capacity, making it perfect for smaller heating or cooling systems. This capacity allows for efficient thermal expansion management without taking up too much space. - Appliance-Grade Finish: The tank is finished with appliance-quality paint, which helps prevent external corrosion and rust. This finish not only enhances the durability of the tank but also adds an aesthetically pleasing look. ## Technical Specifications | Specification | Value | |---------------|-------| | Manufacturer | TT FLEX | | Part number | 4.5Gallon | | Item Weight | 4.24 Kilograms | | Product Dimensions | 22.86 x 22.86 x 33.02 cm; 4.24 kg | | Item model number | 4.5Gallon | | Color | White | | Style | Indoor Installation | | Material | Plastic | | Power source type | no | | Plug Profile | Wall | | Special Features | Prevents Dangerous Build-ups of Pressure, Stops Hot Water from Backflowing into the Cold Water Line, Prevents Hot Water from Escaping through the Pressure Relief Valve and onto the Floor | | Included components | Steel Body,EPDM Diaphragm | | Batteries Included? | No | | Batteries Required? | No | ## Product Details - **Brand:** TT FLEX - **Capacity:** 4.5 Gallons - **Power source:** no - **Product dimensions:** 22.9W x 33H centimeters - **Special features:** Prevents Dangerous Build-ups of Pressure, Stops Hot Water from Backflowing into the Cold Water Line, Prevents Hot Water from Escaping through the Pressure Relief Valve and onto the Floor ## Images ![TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection - Image 1](https://m.media-amazon.com/images/I/51TTO3MiyIL.jpg) ![TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection - Image 2](https://m.media-amazon.com/images/I/615zblPKjsL.jpg) ![TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection - Image 3](https://m.media-amazon.com/images/I/6142p13l4pL.jpg) ![TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection - Image 4](https://m.media-amazon.com/images/I/61TYcDWHtTL.jpg) ![TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection - Image 5](https://m.media-amazon.com/images/I/61udIy4OtYL.jpg) ## Available Options This product comes in different **Model** options. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Review *by A***R on 28 January 2025* All new plumbing in reno so added one inline. So far no issues. Good price. Pressure good so no worries. Easy to add into system ### ⭐⭐⭐⭐⭐ Review *by M***I on 4 December 2024* Funciona ### ⭐⭐⭐⭐⭐ Review *by J***S on 7 April 2026* a larger expansion tank makes hot water work better ## Frequently Bought Together - TT FLEX Potable Thermal Expansion Tank for Water Heater - 4.5 Gallon, 3/4 in MNPT Connection - ZhouDaShu Expansion Tank Mounting Bracket for Hot Water Heater,Thermal Expansion Tank Holder with 2 Earthquake Straps,Support 5-Gallon Hot Water Tanks up to 13 inches in Diameter-1 Set - MEASUREMAN 0-200 PSI Water Pressure Gauge, 2-1/2'' Dial, Hose bib Pressure Gauge, Home Water Pressure Tester, Durable 3/4” Hose Thread, Water Pressure Gauge for Home --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.vu/products/604213502-tt-flex-potable-thermal-expansion-tank-for-water-heater-4](https://www.desertcart.vu/products/604213502-tt-flex-potable-thermal-expansion-tank-for-water-heater-4) --- *Product available on Desertcart Vanuatu* *Store origin: VU* *Last updated: 2026-06-09*